1. Field of the Invention
The invention relates to lubricant and liquid fuel compositions. In particular, it relates to metal hydrocarbyl vicinal diol phosphorodithioates and their use in lubricants to reduce friction and fuel consumption in internal combustion engines.
2. Discussion of the Prior Art
Alcohols are well known for their lubricity properties when formulated into lubricating oils and greases. The use of vicinal hydroxyl-containing alkyl carboxylates such as glycerol monooleate have also found widespread use as lubricity additives. U.S. Pat. No. 2,788,326 discloses some of the esters suitable for the present invention, e.g. glycerol monooleate, as minor components of lubricating oil compositions. U.S. Pat. No. 3,235,498 discloses, among others, the same ester as just mentioned, as an additive to other oils. U.S. Pat. No. 2,443,578 teaches esters wherein the free hydroxyl is found in the acid portion, as for example in tartaric acid.
U.S. Pat. No. 4,044,032 teaches metal salts of certain products made by reacting an alkoxylated alcohol, a polysulfide and a metal sulfide to make additives, but no art is known relating to the compounds of this invention.